By the sustainable management of water, soil and vegetation resources in a watershed unit it can be reached

• a sustained productivity of food, fuel, forage, fibre, fruit;
• a consensus about resource use and possible conflicts (e.g., between upstream and downstream riparians);
• developmental effects (Farrington and James 1998; Förch und Schütt 2004 b; Tidemann 1996).

The watershed unit is explicitly acknowledged by the 'European Water Framework Directive' launched in 2000 (Genskow and Born 2002). This can stand model for other regions (Förch et al. 2005).

The objectives of IWM are introduced next.